RFI - Attachment 3 - Stormwater Management Plan

                                            6.0 Collection And Removal Efficiencies

                                            Stormwater treatment is best when distributed across the catchment treating
                                            stormwater pollutants as close as possible to their point of source. The Ecosol™
                                            Litter Basket provides a cost effective and efficient solution at point of source
                                            and has the highest treatable flow rate of any comparable system. In order to
                                            determine a meaningful characterisation of the Ecosol™ Litter Basket collection
                                            efficiency, an extensive verification phase was undertaken by Avocet Consulting
                                            Pty Ltd, Ecosol and EngTest (The University of Adelaide). To best summarise
                                            the capture efficiency results of extensive product testing a regression of the data
                                            points using a sigmoidal regression curve was selected as it provided a conservative
                                            fit to the wide scatter of data collected. Refer to figures 1 & 2 for testing results.
                                            Table 1 summarises these results

6.1 Particle Size Distribution Collection Efficiency


                    Pollutant Capture Efficiency PSD

                                Capture                    Capture
      Sieve Size
                                Efficiency                 Efficiency
       (micron)
                            (200μm Filter Bag)        (1500μm Filter Bag)

      2000 - 6000                    97%                        97%

      600 - 2000                     97%                        77%

       200 - 600                     86%                        37%

        60 - 200                     35%                        8%

         20 - 60                      4%                        1%




Table 1 – Ecosol™ Litter Basket typical particle size distribution
results at designed Treatable Flow Rates.




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